The curious treatise which is presented in this Guide is the first English translation of the Latin work entitled De Tonitruis (‘On Thunder’), by the Venerable Bede, which outlines a method of brontomantia, or prognostication of the future based on the observation of thunder. Included also in this volume are some short fragments on divination by means of the observance of days, from other works attributed to Bede. This first English translation was taken from Volume 90 of the monumental and ubiquitous Patrologia Latina of J.P. Migne.